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 Solana Beach Coastal Preservation Association
August 20, 1998
Project No. 1831
Page 43
6.6
Reach 6 - Fletcher Cove
Fletcher Cove is bounded by the north and south sides of an ancient canyon, and a bluff of
unconsolidated canyon fill and marine terrace. The Torrey Sandstone, which usually forms
the near-vertical sea cliff is replaced by a Pleistocene-age canyon fill along this reach. The
reach is shown in Map and Photo 7 and 8. Average beach widths within the cove range
from 40 to 60 feet.
6.7
Reach 7 - Las Brisas
The Las Brisas reach is characterized by a large block fall, and extensive notching of the
near-vertical sea cliff. The undermined areas are subject to failure at any time. The reach is
shown in Map and Photo 6 and 7, and represented by Cross Sections 12 and 13, Figures
24 and 25.
The sand beach is almost nonexistent and extends up to elevation 3 feet at the base of the
sea cliff in the overhang. Small areas of shingle beach exist along the base of the cliff.
Offshore, the shore platform appears to have a thin, discontinuous layer of sand. The
near-vertical sea cliff rises to elevation 26 feet. The bluff rises at a slope angle of 39"
degrees to an elevation of 84 feet. A sea-cave infill is being flanked by erosion of the cliff
on both sides.
Comparison of the 1990 and 1998 topographic profiles in Cross Section 12 and 13
suggests the block falls during the El Nio of 1997-98 account for all of the sea-cliff retreat
since 1990. Cross Section 12, at the block fall, indicates 7 feet of retreat, creating an 8.3-
foot high oversteepened scar in the overlying marine terrace deposits. Cross Section 13,
only 37 feet north but outside the block fall indicates no measurable change since 1990.
The deep notches and overhangs could collapse at any time, producing high vertical
scarps in the overlying marine terrace deposits, thus creating severe conditions like those at
Reach 4.
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